2 Points
A biologist began studying a population of bullfrogs. In 1998, she found that
most of the male frogs croaked, but some did not. A bat species known to
prey on male frogs migrated to the area in 2005. The biologist returned to the
area in 2008 and repeated population counts of male frogs. The table shows
her data
1998
2002
2004
2008
Number of
noncroaking males
244
368
298
1086
Number of croaking 742
males
1165
791
305
What factor most likely caused the noncroaking male population to increase
after 2004?
O
A. Extinction of the croakers because of the new predator
O
B. Adaptation of the croakers in the presence of a new predator
O
c. Learning to avoid the new predator
O
D. Selective pressure in the form of a new predator
HELP HELP PLEASE!!

C.The bats response to the croaking behavior of male frogs led to selective pressure against the croaking trait in frogs. Did that help?

Explanation:

question - in 1827, john walker, a druggist in a small english town, tipped a splint with sulphur, chlorate of potash, and sulphid of antimony, and rubbed it on sandpaper, and it burst into flame. the druggist had discovered the first friction-chemical match, the kind we use to-day. it is called friction-chemical because it is made by mixing certain chemicals together and rubbing them. although walker's match did not require the bottle of acid, nevertheless it was not a good one. it could be lighted only by hard rubbing, and it sputtered and threw fire in all directions. in a few years, however, phosphorus was substituted on the tip for antimony, and the change worked wonders. the match could now be lighted with very little rubbing, and it was no longer necessary to have sandpaper upon which to rub it. it would ignite when rubbed on any dry surface, and there was no longer any sputtering. this was the phosphorus match, the match with which we are so familiar. according the paragraph what was the benefit of the new phosphorus match? it burst into flame when rubbed on sandpaper. it was made by mixing chemicals. it could be ignited on any dry surface. it threw fire in all directions.

answer - matches required natural chemicals